The criteria for a standard polypectomy technique for complete removal of small colorectal polyps has not yet been established. This study aimed to compare the complete resection rate of hot snare polypectomy (HSP) with that of EMR for small, sessile, or flat polyps.

Patients with 5- to 9-mm non-pedunculated colorectal polyps were prospectively randomized to the HSP or EMR group. The presence of residual polyps was assessed by performing histologic assessment of 4-quadrant forceps biopsy specimens taken from the edges of the polypectomy site. The primary outcome was the complete resection rate after HSP or EMR; the secondary outcomes were the proportion of procedure-related adverse events and specimen-loss rate. Sample size was estimated using a superiority trial design. We assumed that the complete resection rate of the EMR group would be at least 8% higher than that of the HSP group.

A total of 382 polyps in 269 patients were assessed and randomly assigned to each method using 4 × 4 block randomization. Of these, 353 polyps were finally analyzed based on the pathology results. The mean polyp size was 6.3 ± 1.3 mm. The complete resection rate did not differ between the HSP and EMR groups (88.4% [152/172] vs 92.8% [168/181], respectively; P = .2). The intraprocedural bleeding rate, immediately after polypectomy, was significantly higher in the HSP group than in the EMR group (5.2% vs 0.6%, respectively; P = .009). However, clinically significant bleeding and tissue retrieval failure rates did not differ between the groups. In the multivariate logistic regression analysis, sessile serrated adenoma/polyps or hyperplastic polyps were almost 3 times (odds ratio, 2.824; 95% confidence interval, 1.03-7.75; P = .044) more likely to be incompletely resected compared with other conventional adenomatous polyps. Except for pathology, we found no significant independent predictors for incomplete resection.

EMR for small non-pedunculated colorectal polyps is not superior to HSP in terms of complete resection or safety. Both methods can be performed according to the endoscopist’s preference. (Clinical trial registration number: KCT0001640; cris.nih.go.kr.)